1. Field of the Invention
The present invention relates in general to an effective, quiet and thin bladed heat sink.
2. Description of the Related Art
Due to ever-increasing workloads placed on modern-day computers, combined with higher operating speeds, heat generated by central processing units (CPUs) in computers often reaches extreme levels. As well, the ventilation of the inside of computers is poor so that environmental temperatures of CPUs in operation run high. To avoid failure of CPUs due to overheating, a variety of heat sinks for cooling CPUs have been developed.
Referring to FIG. 1, reference numerals 10 and 30 represent a fan and a central processing unit (CPU), respectively. A conventional heat sink 20 generally is made of metal of good thermal conductivity, and has a base plate 22 and a plurality of fins 21 extending upward from the base plate 22. Referring to FIG. 2, the base plate 22 of the heat sink 20 is fixed to the central processing unit 30, while the fan 10 is supported by the fins 21 of the heat sink 20. The central processing unit 30 in operation generates heat, the heat is transmitted to the heat sink 20 contacting the CPU 30, and the fan 10 generates airflow on the heat sink 20 to dissipate heat. By the arrangement, the central processing unit 30 is cooled.
A conventional heat sink has the following flaws: (1) The airflow is obstructed by the base plate 22 of heat sink 20 and therefore circulates, reducing the efficiency of heat dissipation. (2) So-called xe2x80x9caerodynamic noisexe2x80x9d is increased due to the circulation of hot air. (3) The heat sink 20 is very xe2x80x9cthickxe2x80x9d because of a vertical extension of the fins 21, disadvantageous to mounting the heat sink in a portable computer.
An object of the present invention is to provide a heat sink that dissipates heat very well.
Another object of the present invention is to provide a heat sink that produces minimum aerodynamic noise.
Another object of the present invention is to provide a heat sink suitable for a portable computer.
The heat sink of the present invention includes a connecting board, a plurality of blades, a frame and at least one reinforcing rib. The connecting board is enclosed by the frame. The blades radiate from the connecting board to the frame. Furthermore, the blades are disposed in layers and spaced apart, thereby allowing airflow to pass between the blades. Furthermore, the blades are reinforced by the reinforcing rib.
In operation, a fan blows on the heat sink of the present invention. The airflow rapidly passes through the spaced-apart blades of the heat sink to dissipate heat therefrom. Therefore, the airflow does not circulate, thereby promoting the efficiency of heat dissipation. The arrangement of the blades prevents circulation of hot air and thus minimizes aerodynamic noise. Furthermore, the heat sink of the present invention is thinner because of a horizontal extension of the blades, advantageous to mounting the heat sink in a portable computer.